The present invention pertains to the improvement of a small motor used, for example, as a silent call means, etc., in portable telecommunications equipment and audio equipment (e.g., minidisc players), and it relates to a low-profile coreless motor.
With the adoption of compact, low-profile portable telecommunications equipment and audio equipment (e.g., minidisc players), there also has been a need for compact, low-profile components for mounting in the portable telecommunications equipment. For example, the flat-type vibration motor, which is one means of silent control in portable telecom equipment, is mounted directly on the equipment-side printed-circuit board by means of double-sided tape, an adhesive, etc., so the mounting surface must be flat, and the power-supply terminal that supplies power to the brushes leads to the periphery of the motor. Such a flat-type motor is driven by an axial-direction magnetic field-type ring magnet. This necessitates a power-supply configuration that supplies power to the brushes disposed at the inside diameter of this magnet. As a result, the power-supply configuration that supplies power to the brushes, must be led out between the aforementioned magnet and the bracket, which is part of the housing in which this magnet is mounted.
As disclosed in Japanese Unexamined Patent Application No. 10-262352, such low-profile, coreless vibration motors are such that a recess is formed so as to conform to the shape of the brush base in the bracket by means of press processing, and by embedding the brush base in this recess, the brush base thickness becomes negligible. However, a thick bracket is necessary to form a recess by depressing in press processing. So, in the prior art, the motor thickness has been limited to approximately 2.5 mm. The present invention aims at enabling thinner motors by adding a contrivance to the aforementioned bracket.